Portable battery powered eraser and support therefor

ABSTRACT

A rechargeable cordless eraser comprising a carrier for supporting and electrically charging the eraser when not in use. The eraser includes socket means formed in the housing thereof adjacent one end and having a transverse retainer bar extending between opposite sidewalls of the socket. A pair of charging contact rings are spaced apart longitudinally on the retainer bar. The carrier is adapted to be attached to and supported from a drafting table or the like and includes hook means adapted to extend into the socket means on the eraser between opposite sides thereof and engage the carrier bar. The hook means includes an upwardly opening slot dimensioned for receiving said retainer bar and a pair of deflectable spring contacts are seated in the slot of the hook for supplying charging current to the contacts of the eraser and for biasing the retainer bar against the lower end of the slot to retain the eraser in hanging position on the hook when not in use.

United States Patent Van Acker et al.

[451 Aug. 15, 1972 [54] PORTABLE BATTERY POWERED ERASER AND SUPPORTTHEREFOR I [72] Inventors: John J. Van Acker, Chesterland,

Ohio; Robert E. Zimmer, Niles, Ill.

[73] Assignee: Aph Multigraph Corporation, Mount Propect, Ill.

[22] Filed: July 16, 1971 [21] Appl. No.: 163,179

[52] US. Cl. ..320/2, l5/DIG. l [51] Int. Cl. ..H0lm 45/04 [58] Field ofSearch ..320/2; l5/DIG. l; 30/DIG. l; 32/DlG. 8; 240/ 10.6

[56] References Cited UNITED STATES PATENTS 1,757,889 5/1930 Wheat..320/2 ux 2,622,233 12/1952 Field ..320/2 Primary Examiner-J. D. MillerAssistant Examiner-Robert J. Hickey Attorney-Sol L. Goldstein [57]ABSTRACT A rechargeable cordless eraser comprising a carrier forsupporting and electrically charging the eraser when not in use. Theeraser includes socket means formed in the housing thereof adjacent oneend and having a transverse retainer bar extending between oppositesidewalls of the socket. A pair of charging contact rings are spacedapart longitudinally on the retainer bar. The carrier is adapted to beattached to and supported from a drafting table or the like and includeshook means adapted to extend into the socket means on the eraser betweenopposite sides thereof and engage the carrier bar. The hook meansincludes an upwardly opening slot dimensioned for receiving saidretainer bar and a pair of deflectable spring contacts are seated in theslot of the hook for supplying charging current to the contacts of theeraser and for biasing the retainer bar against the lowerend'of the slotto retain the eraser in hanging position on the hook when not in use.

15 Claims, 7 Drawing Figures PORTABLE BATTERY POWERED ERASER AND SUPPORTTHEREFOR BACKGROUND OF THE INVENTION The present invention relates to anew and improved cordless, rechargeable, battery-powered, portableimplement such as a cordless electric eraser which is used bysecretaries, students, teachers and is especially useful to draftsmen.In many portable implements it is undesirable to have attached powercords connected therewith because it interferes with the free andunencumbered use of the implement. This is especially true with electricerasers in order to easily accomplish an erasing job that may be remotefrom where the implement is stored.

Accordingly, it is desirable and an object of the present invention toprovide a new and improved cordless, rechargeable, battery-powered,electrical implement, more particularly, a cordless electric eraser forgeneral use in offices and schools and hanger thereforthat convenientlyand safely stores the implement when not in use.

It is desirable and an object of the present invention to provide anarrangement whereby a cordless electric eraser or other implement may behandily available for use when desired and, when not in use, may beconveniently and safely stored and supported while the battery is beingrecharged automatically.

In addition, it is desirable to provide a new and improved cordless,portable, electric eraser which can be easily and accurately manipulatedby hand and, when not in use, supported in a recharging carrier whichinsures that proper electrical charging polarity is established whileconveniently supporting the implement in a hanging position in readinessfor the next usage.

Another object of the invention is to provide a new and improvedrecharging support carrier for a portable electric implement, whichcarrier is easily adapted for universal mounting on a fixed object, suchas a desk, drafting table, or wall member and which provides a hookhaving limited flexible movement for ease in hanging up or unhooking therechargeable implement.

BRIEF DESCRIPTION Briefly, the new and improved, rechargeable, portable,electrical implement of the present invention includes a carrier forsupporting the implement and for supplying electrical charging currentto the battery of the implement when in supported position on thecarrier. The carrier is adapted to be mounted in a convenient locationon a table, wall, or structural surface. The cordless electric implementincludes socket means adjacent one end of the casing thereof having atransverse retainer pin or bar extending between opposite sides of thesocket and including a pair of ringlike charging contacts spaced apartlongitudinally on the pin for supplying recharging current to thebattery contained in the housing of the implement.

The support carrier includes a hook means dimensioned as to be receivedinto the socket of the implement. The hook means is formed with anupwardly opening slot for receiving the retaining pin when the implementis hung up for recharging when not in use. A pair of deflectable detentcontacts are mounted in the slot of the hook means for making electricalcontact with and supplying current to the ring contacts on the carrierpin and the deflectable contacts bias the pin against the bottom portionof the hook slot to swingably support the implement in a hangingposition ready for usage. The cooperating hook means and the socketmeans in the implement housing are dimensioned to provide for only oneparticular way of engagement therebetween, and this insures that properpolarity is achieved for supplying charging current to the battery ofthe implement from the contacts in the hook means.

FIGURE DESCRIPTION FIG. 1 is a perspective view illustrating a supportcarrier for automatic recharging of a battery powered electricalimplement as constructed in accordance with the features of the presentinvention;

FIG. 2 is a side elevational view of the support carrier and theportable electric eraser as it is hung up in place while being rechargedautomatically;

FIG. 3 is an enlarged side elevational view of the support carrier withportions broken away and fragmented;

FIG. 4 is a top plan view of the support carrier looking downwardly inthe direction of the arrows 44 of FIG. 2;

FIG. 5 is an outer and elevational view of the support carrier withportions broken away looking in the direction of the arrows 55 of FIG.2;

FIG. 6 .is a fragmentary lower elevational view of the outer end portionof the support carrier looking in the direction of the arrows 66 of FIG.2; and

FIG. 7 is a schematic diagram of an electrical circuit for arechargeable cordless electric eraser of the present invention.

DESCRIPTION Referring now, more particularly, to the drawings, thereinis illustrated a new and improved rechargeable portable electric eraserfor use by draftsmen, and the like. The portable electric eraserincludes an elongated hollow housing 10 (FIG. 2) formed in two partswhich are connected together and are preferably manufactured of moldedplastic material. As shown in FIGS. 2 and 4, the housing parts or halves12 are hollow in order to accommodate a drive shaft 14 having an eraserchuck 16 on the outer end adapted to hold an elongated, cylindrical,rubber eraser 18. The shaft 14 is driven through a pair of reductiongears 20 by a low voltage DC powered electric motor 22. The motor iscontrolled through a control switch 24 having a push button 26 (FIG. 7)which is conveniently located for operator manipulation. The housing orcasing also holds a rechargeable nickel cadmium battery 28.

When not in use, the eraser is adapted to be hung up and supported fromone end of the housing 10 which is shaped to provide a hook-receivingsocket 30 formed in the upper portion of the housing 10. The socket 30is formed by the longitudinal inner socket wall 32, a transverse bottomwall 34 which intersect one another to provide an interior comer and byopposite housing sidewalls 36. A transverse carrier pin 38 forsupporting the eraser in hanging position extends between the oppositesidewalls 36 of the socket.

As shown in FIGS. 2 and 4, a pair of annular contact rings 40 and 42 aremounted on the carrier pin 38 adjacent opposite ends thereof and themidportion on the carrier pin is formed of insulating material to effectelectrical insulation between the pair of contact rings.

As best shown in FIG. 2 and the wiring diagram of the portable electriceraser in FIG. 7, the contact rings are connected to suitable circuitrywithin the eraser housing via contact members 44 and wires 45, 46, 47,48 and 49, for providing charging current for the battery and fordelivering electrical power from the battery to operate the motor 22 ascontrolled by the switch push button 26.

In accordance with the present invention, a carrier assembly 50 (FIG. 1)is provided for supporting the cordless electric eraser when not in useand for automatically charging the battery 28 at this time. The carrierassembly includes a pivotably mounted hook member 52 which is connectedto a fixed base 54 by an elongated, helically coiled spring 56. Thespring connection permits relative pivotal movement between the base andhook members about the longitudinal axis of generation of the helicalspring as well as limited flexible movement between the base and hook inboth directions about axes horizontally and vertically transverse tosaid longitudinal axis of the spring.

As the portable electric eraser is hanging in place or moved into or outof hanging position, this limited flexible movement of the hook providesease ofaction. The base 54 is adapted to be fixedly and permanentlyattached to a drafting table 58 or other structures by means offasteners 60.

The current for recharging the battery 28 in the portable electriceraser is supplied through a line cord 62 having a plug assembly 64 atthe end thereof which is adapted to be inserted into a conventional ACoutlet. The plug assembly 64 contains a rectifier and a voltage reducingcircuit for converting the AC voltage from a convenient outlet to lowvoltage DC current for recharging the battery 28 of the portableelectric eraser.

As best shown in FIG. 3, the hook member 52 includes an upwardly openingcarrier bar receiving slot 66 which is defined by an outer fingerportion 68 ad jacent the outer end. The slot 66 includes parallel sides70 and 72 sloped with respect to the vertical, which are spaced apart adistance slightly larger than the diameter of the carrier bar 38 and thecontact rings 40 and 42 thereon. The lower end of the slot is defined bya closed rounded end or stop surface 74 of substantially the same orslightly larger diameter than the contact rings 40 and 42.

In accordance with the present invention, the carrier pin 38 is biasedtoward the closed lower end 74 of the slot 66 while the cordlesselectric eraser is hung on the hook 52 by a pair of deflectable contactmembers 76 and 78 (FIG. 4). Free end portions of the contacts 76 and 78project outwardly from the rear side 70 of the slot 66 toward theadjacent or front side 72. The contacts 76 and 78 include outer endportions 76a and 78a (FIG. respectively, which are adapted to engage therespective contact rings 40 and 42 and make electrical contact therewithfor charging the battery 28. In addition, the contacts bias the carrierpin downwardly against the lower end surface 74 of the slot 66 in thehook to prevent accidental dislodgment from the hook. As the carrier pin38 is moved into or out of the slot 66, the contacts, and particularlythe end portions 76a and 78a, thereof, are deflected inwardly toward theinside I rear wall surface of the slot and subsequently spring backoutwardly toward the opposite wall 72. The contacts 76 and 78 thusperform a dual function in making electrical contact between therespective wires of the line cord 62 and the contact rings 40 and 42 onthe rechargeable portable electric eraser and, in mechanically holdingand retaining the carrier pin 38 in a downwardly biased conditionagainst the lower end surface 74 of the slot 66 in the hook member 52.

Referring again to FIG. 3, one of the leads of the cord 62 is connectedto the contact 78 at the connection terminal 79. Similarly, the otherlead in the line cord 62 is connected to the contact 76 as best shown inFIG. 5 at the connection terminal 77. The contacts 76 and 78 areconnected to provide for the correct polarity to supply charging currentto the respective contact rings 40 and 42 on the eraser. The respectivecontacts 76 and 78 are mounted in the hook 52 so that the outer free endportions 76a and 78a act against the edges of slots 80 (FIG. 3) formedin the hook member and dimensioned to a width substantially equal to thewidth of the contacts. As best shown in FIG. 3, the contacts are freelydeflectable by the carrier pin and rings 40 and 42 and are preferablyformed of resilient springlike metal having good electrical conductance.

The underside of the hook member 52 is covered by a closure plate 84(FIG. 3) which is held in place by a cap screw 86 which projectsupwardly into a threaded boss portion formed in the hollowed outunderside of the hook member, as best shown in FIG. 3. The hollowed outportion accommodates the forward end of the helically coiled spring 56,and the screw 86 projects upwardly through the forward end loop 56a ofthe spring which is bent transversely to the other coils in the body ofthe spring. The screw 86 thus prevents the forward end of the springfrom rotating relative to the hook member 52 and accomplishes the fixedconnection between the spring 56 and hook member 52.

The intermediate coils of the spring 56 provide a tubular enclosure forenclosing and protecting the line cord 62 which extends forwardly from ahollowed out underside of the fixed base 54 into the hollowed outunderside of the hook member 52. As shown in FIGS. 2, 3 and 4, there isprovided a space between the adjacent facing end surfaces of the baseand hook member and this permits limited lateral deflection of the hookmember 52 in a cantilever fashion relative to the base. The base isusually permanently attached to a convenient support structure, such asthe edge or bottom of a drafting table, and the like, and the springconnection permits the hook member 52 to deflect transversely in avertical direction as well as in a horizontal direction. This actionfacilitates the hanging up of the eraser after usage and makes it easierto guide the carrier pin 38 of the portable electric eraser into theslot 66 of the hook member 52. It should be noted that the stop walls 32and 34 which define the inner socket comer in the eraser housing 10,prevent the improper engagement of the carrier pin within the slot in amanner which might cause reverse polarity of the charging. These wallsare positioned to permit insertion of the hook 52 into the socket 30 inonly one way (shown in FIG. 2), and, when inserted in this manner,correct polarity of current from the charging line cord 62 through thespring contacts 76 and 78 to the contact rings 40 and 42 on the electriceraser is insured.

As best shown in FIG. 3, the rearward end portion of the spring 56extends into the base 54 through a horizontal bore 54a (FIG. 6) andrearwardly thereof the underside of the base is hollowed out, as at 54b(best shown in FIGS. 3 and 6) in order to permit several of rearward endcoils of the spring to freely rotate within the base structure. The rearend of the spring is deformed so that a tang 56b is bent to projectforwardly toward the hook member 52. The tang 56b is adapted to limitthe extent of rotation of the rearward end of the spring 56 about thelongitudinal axis of the spring relative to the base. The tang isengageable with a radially inwardly directed, integrally formed stopmember 54d (FIG. 3) and, accordingly, the relative rotation between thespring 56 and the base 54 is limited to one revolution, or slightlyless, as permitted by the relative position of the tang and stop.

In order to retain the rearward end portion of the coil spring 56 withinthe base 54 and prevent forward withdrawal of the spring, a retaininginsert of thin material as shown as 88, is inserted into a downwardlyopening, thin, transverse slot 540, defined in the underside of the base(FIG. 6). The retaining sheet 88 includes a central aperture thereinslightly larger than the outside diameter of the coils of the spring 56,and the forward end tang 56b is engageable against the retainer toprevent forward withdrawal of the spring from the base.

It will be appreciated that the construction of the carrier assemblyjust described provides a unique and particularly valuable technique forstoring the implement. The hook member is adapted for limited movementsideways, and up and down relative to the base and the implement itselfis swingably mounted in the hook member 52. In the circumstance that themounted implement is suddenly jarred, the nature of the mounting is suchthat it would absorb the sudden movement through the combination of theswinging action of the carrier pin 38 disposed in the slot 66 of thehook member 52 and the pivotable movement of the member 52 relative tothe base 54.

While there has been illustrated and described a single embodiment ofthe present invention, it will be appreciated that numerous changes andmodifications will occur to those skilled in the art, and it is intendedin the appended claims to cover all those changes and modificationswhich fall within the true spirit and scope of the present invention.

What is claimed as new and desired to be secured by Letters Patent Ofthe United States is:

I. In combination, a support carrier for holding an electricallycharging battery powered portable implement, such as cordless electricerasers and the like, said implement including a housing defining asocket means adjacent one end and a transverse retainer bar extendingbetween opposite sides of said socket, means including a pair ofcharging contacts spaced longitudinally on said bar, said carrierincluding hook means adapted to extend into said socket means betweenopposite sides thereof and including an upwardly opening slot forreceiving said retainer bar of said implement, and a pair of deflectablecontacts in said slot for supplying current to said charging contacts onsaid implement and biasing said retainer bar against wall surfaces ofsaid slot to support said implement in hanging position from one endwhile not in use.

2. The combination of claim 1 wherein said carrier including a baseadapted to be attached to a fixed object, such as a table, or the like,and longitudinal connector means interconnecting said base and said hookmeans permitting relative rotation between said hook means and said basearound the longitudinal axis of said connector means.

3. The combination of claim 2 wherein said connector means comprises aspring permitting limited angular deflection between said base and hookmeans transversely of said longitudinal axis.

4. The combination of claim 2 wherein said connector means comprises ahelical coil spring with a plurality of said coils wound around saidlongitudinal axis, at least one end of said coil spring mounted forrotation around said axis relative to said base.

5. The combination of claim 4 including line cord means for supplyingcurrent to said contacts in said hook means, said line cord meansextending between said base and said hook means through the coils ofsaid spring along said longitudinal axis.

6. The combination of claim 5 wherein said line cord means includes plugmeans at the free end for connection to an AC power source and rectifiermeans for converting AC to DC for supply to said contacts.

7. The combination of claim 4 including stop means for limiting rotationof said end coil relative to said base.

8. The combination of claim 1 wherein said socket means is definedadjacent a comer of said one end of said implement and includes at leastone stop wall preventing said hook means from entering said socket meansfrom a wrong direction thereby to insure proper polarity for rechargingsaid implement.

9. The combination of claim 8 wherein said contacts on said retainer barare positioned adjacent opposite sidewalls of said socket means and arespaced apart by a midportion of said bar.

10. The combination of claim 1 wherein said slot in said hook meansincludes a pair of sloped opposite walls terminating in a rounded end,said contacts on said hook means including cam portions projectingoutwardly of one wall toward said opposite wall and sloped to bias saidcarrier bar toward said rounded end.

11. A support carrier for holding and electrically charging a batterypowered portable implement, said implement including a housing defininga socket means adjacent one end thereof, a transverse retainer barextending between opposite sides of said socket, means including a pairof charging contacts spaced longitudinally on said bar, said carriercomprising a fixed base portion and an implement receiving portion,means interconnecting said base and receiving portions comprisingresilient biasing means movably attaching said receiving portion to thebase portion, said receiving portion further including an upwardlyopening slot for receiving said retainer bar of said implement and meansconnecting said charging contacts to a source of electric current.

tively to said base portion and receiving portion permitting limitingangular deflection between said base and receiving portion relative tosaid longitudinal axis.

14. The support carrier of claim 13 including mounting means forsecuring one end of said biasing means to the receiving portionpermitting rotation between the receiving portion and the base,

15. The support carrier of claim 14 including stop means for limitingrotation of said end coil relative to said base biasing means.

2. The combination of claim 1 wherein said carrier including a baseadapted to be attached to a fixed object, such as a table, or the like,and longitudinal connector means interconnecting said base and said hookmeans permitting relative rotation between said hook means and said basearound the longitudinal axis of said connector means.
 3. The combinationof claim 2 wherein said connector means comprises a spring permittinglimited angular deflection between said base and hook means transverselyof said longitudinal axis.
 4. The combination of claim 2 wherein saidconnector means comprises a helical coil spring with a plurality of saidcoils wound around said longitudinal axis, at least one end of said coilspring mounted for rotation around said axis relative to said base. 5.The combination of claim 4 including line cord means for supplyingcurrent to said contacts in said hook means, said line cord meansextending between said base and said hook means through the coils ofsaid spring along said longitudinal axis.
 6. The combination of claim 5wherein said line cord means includes plug means at the free end forconnection to an AC power source and rectifier means for converting ACto DC for supply to said contacts.
 7. The combination of claim 4including stop means for limiting rotation of said end coil relative tosaid base.
 8. The combination of claim 1 wherein said socket means isdefined adjacent a corner of said one end of said implement and includesat least one stop wall preventing said hook means from entering saidsocket means from a wrong direction thereby to insure proper polarityfor recharging said implement.
 9. The combination of claim 8 whereinsaid conTacts on said retainer bar are positioned adjacent oppositesidewalls of said socket means and are spaced apart by a midportion ofsaid bar.
 10. The combination of claim 1 wherein said slot in said hookmeans includes a pair of sloped opposite walls terminating in a roundedend, said contacts on said hook means including cam portions projectingoutwardly of one wall toward said opposite wall and sloped to bias saidcarrier bar toward said rounded end.
 11. A support carrier for holdingand electrically charging a battery powered portable implement, saidimplement including a housing defining a socket means adjacent one endthereof, a transverse retainer bar extending between opposite sides ofsaid socket, means including a pair of charging contacts spacedlongitudinally on said bar, said carrier comprising a fixed base portionand an implement receiving portion, means interconnecting said base andreceiving portions comprising resilient biasing means movably attachingsaid receiving portion to the base portion, said receiving portionfurther including an upwardly opening slot for receiving said retainerbar of said implement and means connecting said charging contacts to asource of electric current.
 12. The support carrier as claimed in claim11 wherein said upwardly opening slot is equipped with a pair ofdeflectable contacts in said slot for supplying current to said chargingcontacts on said implement and biasing said retainer bar against wallsurfaces of said slot to support said implement in hanging position fromsaid one end.
 13. The support carrier as claimed in claim 11 whereinsaid resilient biasing means is a coiled spring extending along alongitudinal axis between said base and receiving portion having itsfree ends fixed respectively to said base portion and receiving portionpermitting limiting angular deflection between said base and receivingportion relative to said longitudinal axis.
 14. The support carrier ofclaim 13 including mounting means for securing one end of said biasingmeans to the receiving portion permitting rotation between the receivingportion and the base.
 15. The support carrier of claim 14 including stopmeans for limiting rotation of said end coil relative to said basebiasing means.